1. Field of the Invention
The present invention relates in general to a traffic generator for evaluating communication characteristics and a method of determining a traffic generating function, and more particularly to a traffic generator for sending a pseudo-traffic to a packet-switched network to evaluate the network performance and a traffic generating function determining method of optimizing generating functions (mathematical models) for a pseudo-traffic.
2. Description of the Related Art
In recent years, the introduction of a network system has progressed, and hence various kinds of applications are operated through the network. Since the scale of the system has been increased and complicated more and more, the application may not be operated as expected and may not be sufficiently confirmed in some cases. For this reason, there has been increased the necessity of evaluating whether or not the resources are effectively utilized.
In general, when carrying out the design and analysis of the network, it is the most effective method to transmit the traffic which is actually sent onto the network by the applications (hereinafter, it may also be referred to as xe2x80x9can actual trafficxe2x80x9d in some cases) through the network as an object of evaluation and the network equipments in order to measure and analyze the traffic.
However, it is difficult in terms of cost to get previously a complete set of necessary applications in order to carry out the evaluation tests. If the actual traffic is employed therefor which is generated by the actual application, then it will be difficult in many cases to carry out the quantitative analysis. For this reason, conventionally, there has been employed a traffic generator for generating a pseudo-traffic which is obtained by imitating the traffic generated by an arbitrary application.
In the case where the packet-switched network becomes an object of evaluation, the characteristics of the traffic which is sent through the various kinds of applications are determined on the basis of both of the packet length and the packet interval. In the conventional traffic generator, since the packet length and the packet interval of the pseudo-traffic are fixed to predetermined values, respectively, it is impossible to generate the pseudo-traffic which is suitable for each of the applications.
The object of the invention is to provide a traffic generator which is capable of setting dynamically both of a packet length and a packet interval of a pseudo-traffic by utilizing a generating function, and a method of determining a traffic generating function.
In order to attain the above-mentioned object, the present invention may provide taking the following measures.
(1) In a traffic generator for sending a pseudo-traffic to a packet-switched network, there are provided: packet length determining means for determining dynamically a packet length of a pseudo-traffic; packet interval determining means for determining dynamically a packet interval of a pseudo-traffic; and pseudo-traffic sending means for generating the pseudo-traffic having both of the packet length and the packet interval thus determined to send the pseudo-traffic onto a network.
According to the traffic generator configured as described above, since both of the packet length and the packet interval of the pseudo-traffic can be arbitrarily set, it is possible to send the pseudo-traffic corresponding to the application as an object of evaluation.
(2) In a traffic generating function determining method of optimizing parameters of mathematical models of a pseudo-traffic, there are provided the steps of: optimizing parameters of first mathematical models on the basis of both of the calculation results of the first mathematical models us ed to define a packet length of the pseudo-traffic and a packet length of an actual traffic generated by an application as an object of evaluation; optimizing parameters of second mathematical models on the basis of the calculation results of the second mathematical models used to define a packet interval of the pseudo-traffic and a packet interval of an actual traffic generated by the application as an object of evaluation; and determining both of the packet length and the packet interval of the pseudo-traffic to be sent on the basis of the first and second mathematical models thus optimized.
According to the traffic generating function determining method designed as described above, since the highly accurate mathematical models can be obtained which are capable of reproducing with accuracy both of the packet length and the packet interval of the actual traffic, respectively, it is possible to generate the pseudo-traffic having both of the packet length and the packet interval which are close to those of the actual traffic, respectively.